Counting chamber



May 7, 1940. c. P. BROWN ET AL COUNTING CHAMBER Filed Feb. 20, 1939Ewen/ions;

67a udef? Brown I z'c K3 7175073 read in conjunction with theaccompanying draw- Patented May 7, 1940 UNITED STATES PATENT OFFICECOUNTING CHAMBER Claude P. Brown and Frederic H. Wilson, Philadelphia,Pa.

Application February 20, 1939, Serial No. 257,278 2 Claims. (Cl. 88-40)The object of the invention is to provide improvements in countingchambers broadly, but more particularly in the clips and frames by whichsuchchambers and the usual cover slips are operatively held,thisapplication being a continuation-in-part of copending applicationSerial No. 212,569, filed June 8, 1933/ Another and. more specificobject with relation to the improved clip resides in oscillatablymounting the entireclip as a unit upon and with respect to a frame, soas to thereby minimize the number of pieces which enter into the clipsconstruction, and at the same time permit the clip to automaticallyadjust its transverse angular position for equalized engagement with acover slip carried by the upper surface of a counting chamber supportedby said frame.

A further object is to provide an improved frame, which may but need notnecessarily be always associated with the said improved clip, said framecomprising a pair of oppositely positioned elements, between which acounting chamber is normally positioned, and a plurality of transverselyextending spacing members, normal- 1y fixedly secured to said elementsbut adjustable with respect thereto, in order to permit the frame as awhole to conform in a transverse direction with the correspondingdimension of counting chambers of various sizes.

With the objects thus briefly stated, the in- I vention consists infurther details of construction and operation, which are hereinafterfully brought out in the following description, when ing, in which Fig.1 is a top plan view of a device comprising one embodiment of theinvention; Fig. 2 is a fragmentary bottom plan View of the samepartially in section; Fig. 3 is a section on the line 3-3 of Fig. 1;Fig. 4 is an enlarged fragmentary side elevational view of the improvedclip, and adjacent portions of the frame; and Fig. 5 is an enlarged sideelevational view of the improved clip and adjacent portions of theframe, counting chamber and cover slip.

Referring to the drawing, one embodiment of the invention is shown ascomprising a base, which in turn is composed of a pair of spacedparallel members I, which may be formed of any suitable material such asa synthetic resin, and provided at spaced regions with transverselyelongated apertures 2, through which extend any suitable form of bolts3, or the like, by which a plurality of spacing members 4 are secured attheir opposite ends to said first members, in such manner that byloosening and re-tightening said bolts, said first-mentioned sidemembers can be brought into close binding engagement with the laterallyoppositesides or the edge portions of an intervening element 5, which ishere shown as comprising a so-called counting chamber. Resilientelement-securingfingers 5 are also preferably provided at spacedintervals, and at one of its ends each of said fingers is fixedlysecured to one of said bolts, whileits oppositely extending free 'endportion engages the-outer surface of the said interposed element.

Although the said element 5 is here shown as comprising a countingchamber, it is to be understood that it may instead comprise any otherelement adapted for operative support by the improved adjustable frame.Similarly, the superimposed cover slip- I, which is usually associatedwith a counting chamber, is here intended to illustrate any secondelement, which is adapted to be lightly maintained upon or inpredetermined fixed relationship with the upper exposed surface of saidfirst element, and for which an improved type of clip has been designed.

This improved clip comprises a central fiat metallic base member 8,provided upon its under surface with an integral or at least aunitarilysecured shaft 9 of curviform cross section, which latter comprises afreely extending portion adapted to slide into and to be normallypositioned within a horizontally arranged bore l0 in one of the sidemembers I of said frame. Said base member 8 of the improved clip is alsoprovided with laterally positioned upwardly extending parallel, ears ll,adjacent to which are positioned a pair of downwardly extending ears I2,forming laterally positioned integral extensions of an oscillatorymember l3, the said last-named member comprising a manually engageabledepressable extension l4, and oppositely and downwardly extending,bifurcated, laterally spaced, free end portions l5, adapted to contactand fixedly position the superimposed element 1 upon and with respect tothe first mentioned element 5. The ears of the respective base andoscillatory members of the improved clip are pivotally connectedtogether by means of a shaft 5, which is surrounded by a suitable coilspring I! of well known design for the purpose of normally maintaining'the laterally. spaced clip extensions IS in depressed operativeposition, and against the tension of which spring it is necessary toexert pressure upon the manually engageable portion M, in order to raisethe extension I5 and release the superimposed element 1.

In the operation of the combined clip and is adapted to oscillatetransversely in a plane parallel with the adjacent side member I andabout the axis of the shaft 9, soas to thereby permit the terminalportions of the finger extensions l5 to rock into equalized engagementwith the surface of the superimposed element 1, whatever such elementmay comprise. It will, therefore, be noted that movement of the clipextensions l5 toward and away from said elements is in a plane angularlydisposed with respect to the plane of oscillation of the clip as a unit,about the axis of the shaft by means of which the clip is detachablyattached to one of said side members.

Having thus described our invention, what we claim as new and desire toprotect by Letters Patent of the. United States is: p

1. The combination of a frame, having a cylindrical bore in a sidethereof, the aids of which bore extends substantially parallel with theplane of said frame, the frame being adapted to support an elementsuperimposed thereupon, with a clip unit comprising a base member havingas its sole support an integral curviform shaft which extends axiallyand rotatably into said bore to permit oscillation of said base memberin a trans verse plane with respect to said first mentioned plane, aspring-actuated bifurcated member having laterally spaced fingersadapted to overlie the frame and the superimposed element, and a pivotmeans upon said base member extending substantially perpendicularly tothe axis of the shaft for pivotally supporting the spring-actuated clipunit comprising a base member having as its sole support an integralcurviform shaft which extends axially and rotatably into said bore topermit oscillation of said base member in a transverse plane withrespect to said first mentioned plane, a spring-actuated bifurcatedmember having a transversely widened free end portion adapted to overliethe frame and the superimposed element, and a pivot means upon said basemember extending substantially perpendicularly to the axis of the shaftfor pivotally supporting the spring-actuated member, the spring-actuatedmember being operative to yieldingly urge the said free end portiontowards the frame and into contact with the superimposed element.

CLAUDE P. BROWN.

FREDERIC' H. WILSON;

